MEET THE GENTLE EXFOLIATING ACID

SO – IN TERMS OF SKINCARE – WHAT DOES LACTIC ACID DO?

It’s good that you specified skincare here, otherwise we might have launched into a monologue about anaerobic respiration. Chris Caires, Chief Scientist at Perricone MD, tells us that lactic acid can do two things for our skin: exfoliation and acne assasination. The former comes from it being an alpha hydroxy acid. As such, lactic acid “is very effective at exfoliating away the top layer of dead skin by dissolving it.” The acne assasination aspect, however, is because lactic acid is also a short-chain fatty acid. “These short chain fatty acids are powerful prebiotics that can selectively kill harmful acne-causing bacteria on skin while leaving good bacteria alone,” he says.

HOW DOES IT COMPARE TO OTHER ALPHA HYDROXY ACIDS?

The large molecule size of lactic acid means “that it doesn’t penetrate deep into the skin cells but works on the surface, making it ideal for more sensitive skin,” says cosmetic scientist and Founder of Oskia, Georgie Cleeve. This is in contrast to glycolic acid, “which is much smaller in molecular size” and therefore does penetrate deep into skin cells. For her, “what makes [lactic acid] so brilliant is that it also hydrates skin.” If you’re more concerned with anti-aging, Lydia Taylor, Elemental Herbology's Education Manager, recommends malic acid: it “will also encourage the production of collagen,” she explains.

WHO WILL BENEFIT FROM USING LACTIC ACID THE MOST?

For Georgie, “lactic acid is ideal as a gentle exfoliator for all skin types that aren’t looking to correct a particular issue” – a bit like those who use dating apps to “have fun and see what happens.” But that’s not to say “what happens” won’t be something special. Lydia advises that lactic acid can indeed “be used for treatment of fine lines and wrinkles, sun-damaged skin, uneven pigmentation and mild acne.” Either way, McKenzie Bolt, Director of Global Education for Biossance, thinks that lactic acid is wonderful for “those wanting a beginning level AHA product” – which may well be you.

IS THERE ANYONE WHO SHOULD AVOID LACTIC ACID?

Although “there are some acids that boost sebum production, making them unsuitable for oily skin types,” says Georgie, “lactic is the one acid that is suitable for all.” But “you should just be careful to not overuse it as this can cause irritation,” cautions Lydia.